Devices and methods for controlled release of substances

ABSTRACT

A controlled release device and method of use, the device comprising a reservoir wherein the reservoir is divided into one or more chambers; a first active material placed in a first chamber of the one or more chambers and at least one second active material placed in at least one other of the one or more chambers wherein the first active material comprises an active ingredient (AI), wherein the AI is one of an insecticide, a spatial repellent, a herbicide or a larvicide; wherein the at least one second active material comprises one or both of a matrix and an altering material; a permeable membrane covering the first chamber; partitions positioned between adjacent chambers of the one or more chambers for dividing the reservoir into chambers such that full or partial removal of one or more of the partitions results in mixing of the first active material and the at least one second active material to form a mixed active material; a cap positioned over the membrane for sealing the reservoir such that removal of the cap results in controlled release of the AI from the mixed active material through the membrane.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 371 application from international patentapplication PCT/IB2019/052121 filed Mar. 15, 2019, and is related to andclaims the benefit of priority from U.S. Provisional patent application62/643,769 filed Mar. 16, 2018, which is incorporated herein byreference in its entirety.

FIELD

Embodiments disclosed herein relate to devices and systems forcontrolled release of active ingredients (AI) into a fluid environment.

BACKGROUND

The problem of delivering AIs in a controlled release manner is knownand has been addressed in the past in various ways such as controlledrelease devices (CRD) for vector control in agricultural, military, orcivilian applications.

An example showing efficacy of CRDs is given in Stevenson, Jennifer C.,et al. “Controlled release spatial repellent devices (CRDs) as noveltools against malaria transmission: a semi-field study in Macha,Zambia.” Malaria journal 17.1 (2018): 437. Another example of CRDimplementation is given in Bernier, Ulrich, et al. “CombinedExperimental-Computational Approach for Spatial Protection EfficacyAssessment of Controlled Release Devices against Mosquitoes(Anopheles),” PLoS Negl Trop Dis. 2019 Mar. 11; 13(3).

The challenges facing development of effective CRDs include: controllingthe release rate of the AI from within the CRD, and preventingactivation or combination of the AI and other components within the CRDuntil the CRD is deployed. Further, there is a need to deliver CRDs thatare inexpensive, environmentally friendly, and easy to manufacture andassemble.

SUMMARY

Exemplary embodiments disclosed herein relate to a device, system andmethod for controlled release of an active ingredient by active orpassive mechanisms. Some exemplary embodiments provide for CRDs withmultiple mechanisms for controlling the release rate of an AI fromwithin the CRD and also mechanisms for preventing activation orcombination of the AI and other components within the CRD until the CRDis deployed.

In some exemplary embodiments, the devices can be implemented aswearable devices for protection against vectors such as mosquitoes andticks. In some exemplary embodiments, the devices can be deployed forapplications such as: households for indoor or outdoor use; agriculturalapplications, for example to protect against multiple vectors thataffect crops, such as weevils, or psyllids by attachment to a tree ordeployment in soil; weed eradication such as use of herbicides providedin low dosage, low toxicity deliveries; floating devices to disperselarvicides to remove larvae from water; and so forth. In some exemplaryembodiments, a device is manufactured from biodegradable,environmentally friendly materials.

In exemplary embodiments, a controlled release device (CRD) comprises: areservoir wherein the reservoir is divided into a plurality of chambers;a first active material placed in a first chamber of the plurality ofchambers and at least one second active material placed in at least oneother of the plurality of chambers wherein the first active materialcomprises an active ingredient (AI), wherein the at least one secondactive material comprises one or both of a matrix and an alteringmaterial; a permeable membrane covering the first chamber; partitionspositioned between adjacent chambers of the plurality of chambers fordividing the reservoir into chambers such that full or partial removalof one or more of the partitions results in mixing of the first activematerial and the at least one second active material to form a mixedactive material; and a cap positioned over the membrane for sealing thereservoir such that removal of the cap results in controlled release ofthe AI from the mixed active material through the membrane.

In exemplary embodiments, the AI is one of transfluthrin or metofluthrinand the altering material of the at least one second active material isa volatile organic solvent such that the mixed active material isvolatized transfluthrin.

In exemplary embodiments, the AI is one of transfluthrin or metofluthrinand the altering material of a first of at least one second activematerial is a volatile organic solvent and the altering material of asecond of at least one second active material is DMSO such that themixed active material is volatized transfluthrin or metofluthrinenhanced by DMSO.

In exemplary embodiments, the AI is one of transfluthrin or metofluthrinand the first active material further comprises DMSO for enhancing thetransfluthrin wherein the altering material of the at least one secondactive material is a volatile organic solvent such that the mixed activematerial is volatized transfluthrin or metofluthrin enhanced by DMSO.

In exemplary embodiments, the volatile organic solvent is one ofisopropanol, ethanol, methanol, or hexane. In exemplary embodiments, theAI is provided in a concentration of between 20%-95% of the mixed activematerial.

In exemplary embodiments, the altering material of a first of the atleast one second active material is an exothermic reactant such that themixed active material is the AI at an increased temperature.

In exemplary embodiments, the AI is transfluthrin and the alteringmaterial of a first of at least one second active material is a volatileorganic solvent and the altering material of a second of at least onesecond active material is an exothermic reactant such that the mixedactive material is volatized transfluthrin that is further volatized byincreased temperature caused by the exothermic reactant.

In exemplary embodiments, the exothermic reactant is provided in theform of powder or rods selected from the group consisting of: iron,iron-based compounds, vermiculate (hydrated magnesium aluminumsilicate), charcoal powder, and sodium chloride. In exemplaryembodiments, the exothermic reactant is an exothermic reactant that isactivated when exposed to oxygen such that the exothermic reactant isactivated when the cap is removed.

In exemplary embodiments, the AI is one of an insecticide, a spatialrepellent, a herbicide or a larvicide. In exemplary embodiments, the atleast one second active material comprises an AI.

In exemplary embodiments, the cap is attached to the partitions suchthat removal of the cap results in removal of the partitions for mixingof the first active material and the at least one second active materialto form a mixed active material.

In exemplary embodiments, the device of is adapted for sequential mixingof the first active material and the at least one second active materialbefore release of the mixed active material wherein the adaptationcomprises the cap can only be removed after the partitions are removed.

In exemplary embodiments, the first active material further comprisesone or both of a matrix and an altering material.

In exemplary embodiments, the controlled release is determined by acontrolled release mechanism selected from the group consisting of:changing the evaporation rate of the AI, changing the surface area ofthe matrix, changing the permeability of the membrane, adding one ormore diffusion barriers, changing the viscosity of the first activematerial, changing the type of matrix, changing the temperature of thereservoir, utilizing an active release mechanism, changing theformulation of the first active material, changing the formulation ofthe at least one second active material, changing the permeability ofthe plurality of partitions, and a combination thereof.

In exemplary embodiments, the AI is selected from the group consistingof: a spatial repellent, an essential oil, a pyrethroid, an insecticide,an organochloride, an organophosphate, a carbamate, a neonicotinoid, aherbicide, an attractant, a larvicide, and a combination thereof.

In exemplary embodiments, the altering material is selected from thegroup consisting of: a solvent, an encapsulator, an enhancer, anexothermic reactant, an oil and a combination thereof.

In exemplary embodiments, the matrix is selected from the groupconsisting of: a porous material, a material with a high surface tovolume ratio, a synthetic material, a material reactive to the alteringmaterial, and a combination thereof.

In exemplary embodiments, the device further comprises at least onediffusion barrier. In exemplary embodiments, the diffusion barriercomprises at least one hydrophobic domain.

In exemplary embodiments, a cap release mechanism is selected from thegroup consisting of: a mechanical cap release mechanism, a breakable caprelease mechanism, an electrothermal rupture release mechanism, anelectro-thermal-stress rupture release mechanism, an ultrasound caprelease mechanism, a pH-based cap release mechanism, an optical-basedrelease mechanism, and a combination thereof.

In exemplary embodiments, the device is adapted to be wearable. Inexemplary embodiments, the device further comprises a buoyancy mechanismcomprising an air chamber and a stabilizer for deployment of the devicein a liquid. In exemplary embodiments, the device further comprises aparachute connected to the cap such that release of the CRD from aflying platform will result in opening of the parachute to thereby pullopen the cap such that the AI is released.

In exemplary embodiments, the device further comprises an indicator forshowing the amount of AI remaining in the device wherein the indicatorcomprises a scale and a dye calibrated to have the same volatility asthe mixed active material to thus show the remaining concentration of AIin the device.

In exemplary embodiments, a controlled release device for controlledrelease of an AI in a liquid comprises: a reservoir; a first activematerial positioned in the reservoir wherein the first active materialcomprises the active ingredient (AI), wherein the AI is one of aninsecticide, a spatial repellent, a herbicide or a larvicide; and abuoyancy mechanism comprising an air chamber and a stabilizer.

In exemplary embodiments, the device comprises a superhydro/oleic-phobic material outer layer.

In exemplary embodiments, a CRD for deployment from a flying platformcomprises: a reservoir; a first active material positioned in thereservoir wherein the first active material comprises an activeingredient (AI), wherein the AI is one of an insecticide, a spatialrepellent, a herbicide or a larvicide; and a parachute connected to acap covering pores of the reservoir such that release of the CRD from aflying platform will result in opening of the parachute to thereby pullopen the cap to thereby expose the pores such that AI is released.

In exemplary embodiments, a CRD comprises; a reservoir divided into aplurality of chambers; a plurality of active materials each placed inone of the plurality of chambers wherein each of the plurality of activematerials comprises an AI, wherein the AI is one of an insecticide, aspatial repellent, a herbicide or a larvicide; and pores from each ofthe plurality of chambers for release of the AI from each of theplurality of active materials through the pores.

In exemplary embodiments, the pores are positioned so as to be exposedwhen the CRD is inserted into periodically spaced weavings of a vest. Inexemplary embodiments, the vest is a US military standard vest.

In exemplary embodiments, the number of the pores corresponding to eachof the plurality of chambers are adapted to change the release rate ofthe AI from the corresponding chamber. In exemplary embodiments, thesize of the pores corresponding to each of the plurality of chambers isadapted to change the release rate of the AI from the correspondingchamber. In exemplary embodiments, the percentage concentration of theAI in each of the plurality of chambers is adapted to change the releaserate of the AI from the corresponding chamber.

In exemplary embodiments, the CRD is adapted to be wearable. Inexemplary embodiments, the CRD further comprises an indicator forshowing the amount of AI remaining in each of the plurality of chambersof the device wherein the indicator comprises a scale and a dyecalibrated to have the same volatility as the active material in each ofthe plurality of chambers to thus show the remaining concentration of AIin each of the plurality of chambers.

In exemplary embodiments, there are provided methods for integrating anAI with a high melting point into a matrix comprising: warming the AI toits liquid form; soaking the matrix with the liquid AI; and enablingcooling of the soaked matrix such that the AI solidifies integrated intothe matrix.

In an exemplary method embodiment, the AI is transfluthrin. In anexemplary method embodiment the cooling is active cooling or passivecooling.

In exemplary embodiments, there are provided methods for integrating anAI with a high melting point into a matrix comprising: combining the AIwith a solvent to liquefy the AI; soaking the matrix with the liquidAI-solvent mixture; and enabling evaporation of the solvent such thatthe AI solidifies integrated into the matrix. In an exemplary methodembodiment the AI is transfluthrin.

In exemplary embodiments, a controlled release device comprises: areservoir; a first active material positioned in the reservoir whereinthe first active material comprises an active ingredient (AI) whereinthe AI is one of an insecticide, a spatial repellent, a herbicide or alarvicide; a permeable membrane covering the reservoir; and a cappositioned over the membrane for sealing the reservoir such that removalof the cap results in controlled release of the AI from the first activematerial through the membrane.

In exemplary embodiments, the first active material further comprisesone or both of a matrix and an altering material.

In exemplary embodiments, the controlled release is determined by acontrolled release mechanism selected from the group consisting of:changing the evaporation rate of the first active material, changing thesurface area of the matrix, changing the permeability of the membrane,adding one or more diffusion barriers, changing the viscosity of thefirst active material, changing the type of matrix, changing thetemperature of the reservoir, utilizing an active release mechanism,changing the formulation of the first active material, and a combinationthereof.

In exemplary embodiments, the AI is selected from the group consistingof: a spatial repellent, an essential oil, a pyrethroid, an insecticide,an organochloride, an organophosphate, a carbamate, a neonicotinoid, aherbicide, an attractant, a larvicide, and a combination thereof.

In exemplary embodiments, the altering material is selected from thegroup consisting of: a solvent, an encapsulator, an enhancer, anexothermic reactant, an oil and a combination thereof.

In exemplary embodiments, the matrix is selected from the groupconsisting of: a porous material, a material with a high surface tovolume ratio, a synthetic material, a material reactive to the alteringmaterial, and a combination thereof.

In exemplary embodiments, the device further comprises at least onediffusion barrier. In exemplary embodiments, the diffusion barriercomprises at least one hydrophobic domain.

In exemplary embodiments, the cap hermetically seals the reservoir.

In exemplary embodiments, a cap release mechanism is selected from thegroup consisting of: a mechanical cap release mechanism, a breakable caprelease mechanism, an electrothermal rupture release mechanism, anelectro-thermal-stress rupture release mechanism, an ultrasound caprelease mechanism, a pH-based cap release mechanism, an optical-basedrelease mechanism, and a combination thereof.

In exemplary embodiments, the device is adapted to be wearable. Inexemplary embodiments, the device comprises a buoyancy mechanism fordeployment of the device in a liquid. In exemplary embodiments, thedevice is adapted for deployment from a flying platform and wherein theadaptation comprises a parachute. In exemplary embodiments, thereservoir is formed from a fold-up container.

In exemplary embodiments, the device further comprises an indicator forshowing the amount of AI remaining in the device wherein the indicatorcomprises a scale and a dye calibrated to have the same volatility asthe active material to thus show the remaining concentration of AI inthe device.

Implementation of the method and system of the present inventioninvolves performing or completing certain selected tasks or stepsmanually, automatically, or a combination thereof.

Unless otherwise defined, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art to which this invention belongs. The materials, methods, andexamples provided herein are illustrative only and not intended to belimiting.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects, embodiments and features disclosed herein will become apparentfrom the following detailed description when considered in conjunctionwith the accompanying drawings. Like elements may be numbered with likenumerals in different FIGS.:

FIG. 1A shows an exemplary embodiment of a CRD with a cap on;

FIG. 1B shows an exemplary embodiment of a CRD with a cap off;

FIG. 1C shows a sectional illustration of an exemplary embodiment of aCRD with a single chamber;

FIG. 1D, FIG. 1E and FIG. 1F show exemplary embodiments of a CRD with adiffusion barrier;

FIG. 2A and FIG. 2B show sectional illustrations of an exemplaryembodiment of a CRD with two chambers;

FIG. 3A and FIG. 3B show sectional illustrations of an exemplaryembodiment of a CRD with three chambers;

FIG. 4A and FIG. 4B show flowcharts of a process for integrating an AIwith a high melting point into a matrix;

FIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D show alternate views and anexploded view of an exemplary embodiment of a CRD;

FIG. 5E shows a graph of exemplary dispersion rates for a CRD withmultiple chambers;

FIG. 5F and FIG. 5G show photographs of an exemplary CRD adapted forattachment to clothing;

FIG. 6 shows an exemplary embodiment of a CRD for deployment into afluid environment;

FIG. 7 shows an exemplary embodiment of a CRD for deployment from anflying platform; and

FIG. 8A, FIG. 8B, FIG. 8C and FIG. 8D show an exemplary embodiment of aCRD formed from a fold-up reservoir.

DETAILED DESCRIPTION

Exemplary embodiments relate to a system, device and method forcontrolled release of an active ingredient (AI) from a reservoir into afluid environment. In some exemplary embodiments, the reservoir iswearable. Exemplarily, the fluid environment is air. In exemplaryembodiments, the AIs of the present disclosure serve for any one ofspatial repellents, insecticides, herbicides, larvicides, or acombination of these. Optionally, the devices of the present disclosureserve for the release of AIs with other functions.

FIG. 1A shows an exemplary embodiment of a CRD with a cap on and FIG. 1Bshows an exemplary embodiment of a CRD with a cap off. As shown, areservoir 110 of a CRD 100 houses an active material 120. Activematerial 120 comprises an active ingredient 122 and other materials asfurther described herein. Reservoir 110 is covered by a permeablemembrane 114. Membrane 114 comprises release pores 112 which are coveredfor preventing release of AI 120 by a sealing cap 130. Pores 112 areshown in FIGS. 1A-1B as rectangular, but may optionally be of any shape.Pores 112 are optionally sized so as to control the release kinetics ofAI 122. Pores 112 are shown herein as visible openings but areoptionally microscopic permeable paths through permeable membrane 114.

FIG. 1A shows sealing cap in position on reservoir 110 and FIG. 1B showssealing cap 130 removed for release of AI 120 through pores 112. Cap 130comprises a cap release mechanism 132 which is shown here as a pull tabfor pulling off cap 130 where cap 130 is attached for example by anadhesive to reservoir 110. In some embodiments, cap 130 can be replacedonto reservoir 110 after being removed, to reseal reservoir 110. Inother embodiments, cap 130 cannot be replaced onto reservoir 110 toreseal reservoir 110 after being removed.

Optionally, cap release mechanism 132 may be any one of:

-   -   A mechanical cap release mechanism, where cap 130 is held onto        reservoir by means known in the art such as a screw cap or pull        cap;    -   A breakable cap release mechanism, where cap 130 is adapted to        be broken open by a user using mechanical force such as by        having pre-scored sections;    -   An electrothermal rupture release mechanism, such as published        in Elman, N. M., et al. “Electro-thermally induced structural        failure actuator (ETISFA) for implantable controlled drug        delivery devices based on Micro-Electro-Mechanical-Systems.” Lab        on a Chip 10.20 (2010): 2796-2804, where cap 130 comprises a        base material, for example, silicon nitride, and one or more        planar fuses comprising, for example, titanium, gold, and/or        copper, that are placed across the base material. Upon applying        an electrical pulse with a given current, the fuses break and        cap 130 then breaks open due to the thermo-electric reaction;    -   An electro-thermal-stress rupture release mechanism, where cap        130 comprises a base material, for example silicon nitride, and        one or more fuses comprising, for example, titanium, gold and/or        copper, where fuses are positioned in the inner perimeter of cap        130 where typically (together with the center) the mechanical        stress is at its highest. By applying a voltage to the fuses,        the fuses act as resistors thereby dissipating heat which is        transferred to cap 130, forcing cap 130 to expand beyond the        yield strength of the base material, thereby breaking open cap        130;    -   An ultrasound cap release mechanism, where sound waves are        applied with enough energy to break cap 130 by matching the        applied sound frequency to the resonant frequency of cap 130.        Optionally, where more than one cap 130 is provided, each cap        130 is characterized by a different resonant frequency to enable        selective breaking open of each cap 130. Optionally, additional        structural features could be added to a cap, e.g. additional        rectangular features to pre-define such changes in resonance        frequencies without changing the lateral dimensions of cap 130;    -   A pH-based cap release mechanism, where cap 130 comprises        materials prone to react with a given environmental pH to        degrade until the mechanical structure of cap 130 is fully        compromised. In a non-limiting example, a device 100 for release        of an AI 122 into water could rely on the water pH to chemically        degrade cap 130;    -   An optical-based release mechanism, where cap 130 is burst using        optical energy such as a laser.

Cap 130, reservoir 110 and membrane 114 may be transparent,semi-transparent or opaque. Cap 130 and reservoir 110 are here shown assemi-transparent for clarity. In some exemplary embodiments, cap 112hermetically seals reservoir 110. In some exemplary embodiments,reservoir 110 and cap 130 are formed of a non-porous material.

In the illustrative drawing of FIGS. 1A-1B, reservoir 110 is shown ashaving a rectangular form, but this should not be considered limitingand reservoir 110 and the active material 120 therein may optionallyhave any required shape such as shown in FIG. 1E (a top-downcross-sectional view of circular device 100).

FIG. 1C shows a sectional illustration of an exemplary embodiment of aCRD with a single chamber. Device 100 is provided with active material120 comprising an AI 122, an optional matrix 124, and/or an optionalaltering material 126. Altering material 126 may comprise solvents,oils, enhancers, exothermic reactants, encapsulators, excipients, or acombination of these. It should be understood that where AI 122 iscombined with altering materials 126, that device 100 maydiffuse/release AI 122 as well as altering materials 126. CRD 100optionally includes an indicator 108 showing the amount of AI 122remaining in CRD 100. Indicator 108 is optionally a window into device100 with a scale and a dye calibrated to have the same or similarvolatility as the formulation of active material 120 to thus show theremaining concentration of AI 122.

FIG. 1C shows active material 120 comprising a matrix 124 having equallysized and spaced cells. It should be appreciated that matrix 124 asshown is illustrative, and that AI 122 and other materials willtypically be mixed together at a molecular level and spread throughoutmatrix 124. The active material may be optionally provided in a gelform.

In the embodiment of FIGS. 1C-1E, reservoir 110 comprises a singlechamber. In such an embodiment, where active material 120 comprises analready-mixed formulation, reservoir 110 is hermetically sealed by cap130 so as to prevent release or activation of active material 120.Exemplary embodiments with more than one chamber are described below.

In some exemplary embodiments, matrix 124 comprises a porous (sponge)material, for example but not limited to cellulose. Matrix 124 holds AI122 by absorption-adsorption mechanisms. Matrix 124 is optionallyprovided with a high surface to volume ratio for increasing the surfacearea for evaporation of AI 122. Matrix 124 optionally adsorbs/absorbs AI122 for altering the release rate of AI 122. Matrix 124 optionallycomprises a synthetic material such as but not limited to Polyurethane(ether & ester grades), Micro-Cellular Urethanes, ReticulatedPolyurethane Foam Filters, Crosslink Polyethylene Roll Stock, CrosslinkPolyethylene, and/or Polyurethane.

Optionally, matrix 124 is reactive to an altering material 126 such as asolvent, such that matrix 124 dissolves or is biodegraded at a givenrate thereby releasing AI 122 contained therein. As a non-limitingexample, a matrix 124 of cellulose sponge can react with an acetonesolvent.

In some exemplary embodiments, AI 122 comprises a spatial repellent,insecticide, herbicide, larvicide, or a combination of these. AI 122 maybe any one of, or a combination of, but is not limited to:

-   -   Essential oils such as citronella, geraniol, lemon grass,        peppermint, cedar oil, eugenol;    -   A pyrethroid such as metofluthrin, transfluthrin, Allethrin,        Bifenthrin, Cyhalothrin, Lambda-cyhalothrin, Cypermethrin,        Cyfluthrin, Deltamethrin, Etofenprox, Fenvalerate, Permethrin,        Phenothrin, Prallethrin, Resmethrin, Tetramethrin, Tralomethrin;    -   An insecticide, such as imidacloprid, Heptachlor,        Hexachlorobenzene, Lindane (gamma-hexachlorocyclohexane),        Methoxychlor, Mirex, Pentachlorophenol, TDE;    -   An organochloride, such as Aldrin, Chlordane, Chlordecone, DDT,        Dieldrin, Endosulfan, Endrin;    -   An organophosphate, such as Acephate, Azinphos-methyl,        Bensulide, Chlorethoxyfos, Chlorpyrifos, Chlorpyriphos-methyl,        Diazinon, Dichlorvos (DDVP), Dicrotophos, Dimethoate,        Disulfoton, Ethoprop, Fenamiphos, Fenitrothion, Fenthion,        Fosthiazate, Malathion, Methamidophos, Methidathion, Mevinphos,        Monocrotophos, Naled, Omethoate, Oxydemeton-methyl, Parathion,        Parathion-methyl, Phorate, Phosalone, Phosmet, Phostebupirim,        Phoxim, Pirimiphos-methyl, Profenofos, Terbufos,        Tetrachlorvinphos, Tribufos, Trichlorfon;    -   A carbamate, such as Aldicarb, Bendiocarb, Carbofuran, Carbaryl,        Dioxacarb, Fenobucarb, Fenoxycarb, Isoprocarb, Methomyl,        2-(1-Methylpropyl)phenyl methylcarbamate;    -   A neonicotinoid, such as Acetamiprid, Clothianidin,        Imidacloprid, Nitenpyram, Nithiazine, Thiacloprid, Thiamethoxam,        Anabasine, Anethole, Annoninm Asimina for lice, Azadirachtin,        Caffeine, Carapa, Cinnamaldehyde, Cinnamon leaf oil, Cinnamyl        acetate, Deguelin, Derris, Desmodium caudatum, Eugenol,        Linalool, Myristicin, Neem (Azadirachtin), Nicotiana rustica        (nicotine), Peganum harmala, seeds (smoke from), root, Oregano        oil, Polyketide, Pyrethrum, Quassia, Tetranortriterpenoid,        Thymol.    -   A herbicide, such as glycphosates and/or paraquat, and/or    -   A larvicide, such as Bacillus thuringiensis israelensis (BTI).

Optionally, altering material 126 is a solvent. A solvent optionallyprovides for dilution of AI 122 and further optionally for a potentialincrease in volatilization of the compounded formulation by anazeotropic mixture for which the evaporation temperature of theresultant mixture is lower than that of AI 122 by itself. Optional nonlimiting examples of an AI 122 combined with an altering material 126where altering material 126 is a solvent include: metofluthrin andisopropanol, or transfluthrin and an alcohol. Optionally, AI 122 issolid at room temperature due to a relatively high melting point and asolvent provides for an improvement in the volatilization by relying ona phase change from liquid to vapor, instead of solid to vapor. Anon-limiting example of an AI 122 that is solid at room temperature istransfluthrin which has a melting point of 32 degrees Celsius. Anon-limiting method for integrating such a solid AI 122 into a matrix124 is described below with reference to FIGS. 4A-4B. In a formulationof an AI 122 of transfluthrin or metofluthrin with a volatile organicsolvent, the AI is provided in a range of 20%-95% of the formulation andthe solvent in a corresponding range of 80% to 5%. Optionally, alteringmaterial 126 is an encapsulator/emulsion. Combination of AI 122 with anencapsulator results in a particle that degrades over time for long orshort-term release of the AI 122 inside depending on the rate ofdegradation. Additionally or alternatively, an encapsulator is combinedwith AI 122 to become a porous particle (similar to matrix 124) forcontaining AI 122 and providing a barrier for rapid evaporation of AI122 to further regulate the release rate of AI 122. A further advantageof an encapsulator is that the encapsulator AI mixture may be pouredinto reservoir 110 where it sets, to thereby adapt to the form ofreservoir 110 and simplify manufacture of device 100. Non-limitingexamples of encapsulators include: nano/microparticle or emulsions ofPLGA (Poly Lactic-co-Clycolic Acid), poly(lactid) acid (PLA), chitosan,liposomes, CaCO₃ particles, silicon/silica particles, and/or alginate.An example of a combined encapsulator and AI 122 is PLGA andimadacloprid (an insecticide).

Optionally, altering material 126 is an enhancer for combination with AI122 that makes AI 122 more effective. A non-limiting example of anenhancer is DMSO (dimethylsulfoxide) that provides for improvedpenetration and uptake of an insecticide combined with DMSO, in targetinsects.

Optionally, altering material 126 is an exothermic reactant. AI 122 iscombined with an exothermic altering material 126 resulting inexothermic reactants increasing the temperature of the active material120 upon exposure to oxygen, such as when cap 130 is removed. Increasedtemperature typically increases the evaporation rate. Non-limitingexamples of exothermic reactants include powder or rods comprising iron(for exothermic oxidation of the iron when exposed to air), aniron-based compound, vermiculate (hydrated magnesium aluminum silicate),charcoal powder, and sodium chloride.

Optionally, altering material 126 is an oil. Use of an oil typicallyreduces volatility of the AI. A non-limiting example of such acombination is a pheromone of high volatility and an oleic acid.

FIG. 1D, FIG. 1E and FIG. 1F show exemplary embodiments of a CRD with adiffusion barrier. In some exemplary embodiments, such as shown in FIGS.1D-1F, device 100 comprises a diffusion barrier 116 that surrounds partor all of active material 120. Diffusion barrier 116 prevents leakage ordiffusion of active material 120 such as where reservoir 112 is porous.In some exemplary embodiments, diffusion barrier 116 acts as a secondaryrelease mechanism by absorbing AI 122 and releasing AI 122 at a requiredrelease rate. In some exemplary embodiments, more than one diffusionbarrier is provided such as illustrated in FIG. 1E with concentricbarriers 116A and 116B. When acting as a secondary release mechanism,diffusion barrier 116 optionally includes hydrophobic domains 118 (FIG.1F), located on the inner walls of barrier 116 to absorb AI 122 frommatrix 124, followed by controlled release of AI 122 from barrier 116.

In some exemplary embodiments, active material 120, once inserted insidediffusion barrier 116, becomes suspended and does not make any directcontact with the top or bottom surfaces of reservoir 110, preventingthese surfaces from becoming wet from contact with the active material120. Active material 120 optionally expands and the frictional forcebetween the expanded active material 120 and barrier 116 is such thatactive material 120 is secured and restrained from moving, even whendevice 100 is dropped. Moreover, in some exemplary embodiments,diffusion barrier 116 can have one closed end, like a cap. Moreover,some exemplary embodiments of device 100 may include multiple diffusionbarriers 116 each holding different active materials 120, allowingmultiple formulations of active materials 120 and multiple controlledrelease profiles.

Device 100 thus provides sustained release of the active ingredient byactive or passive mechanisms. A passive controlled release primarilyrelies on diffusion and natural convection as the main transfer processfrom reservoir to outside fluid. It should therefore be appreciated thatthe device 100 provides multiple mechanisms for controlling the passiverelease of an AI including:

-   -   Changing the evaporation rate of the mixture by altering the        formulation of active material 120, such as by adding one or        more altering materials 126 as described above;    -   Changing the surface area of the matrix 124 material, such as        increasing the surface area to create a greater area for        evaporation to thereby increase the release rate;    -   Changing the permeability of membrane 114, such as choosing a        membrane with visible pores 112 for increased release rate or a        dense membrane 114 to lower the release rate;    -   Adding one or more diffusion barriers 116 and varying the        thicknesses, absorption rates, diffusion rates, and exposed        surface areas of diffusion barriers 116;    -   Changing the viscosity of the AI 122 and altering material 126        by changing the formulation of active material 120;    -   Changing the type of matrix 124, such as increasing or        decreasing the porosity/permeability of matrix 124. For example,        cellulose, which provides a large internal surface area and        structural porosity, will cause the formulation to be adsorbed        or absorbed and held while limiting the diffusion across the        matrix, as well as modulating the overall volatilization.

An active controlled release system can rely on all the characteristicsand parameters of the passive system combined other active systems suchas:

-   -   Changing the temperature of the reservoir 110 and/or reaction        between the materials, such as where altering material 126 is an        exothermic reactant;    -   Utilizing active release mechanisms, such as but not limited to        a battery and a hot plate (not shown) to increase the        temperature of active material 120 to increase volatility of AI        122, or a powered fan (not shown) to provide forced convection        to increase mass transfer rates of AI 122.

FIG. 2A and FIG. 2B show sectional illustrations of an exemplaryembodiment of a CRD with two chambers. A device 200 provides forcontrolled release of an AI. Device 200 is functionally similar todevice 100 but reservoir 110 comprises two internal chambers 244 and 246divided by an internal partition 240. A first chamber 244 contains afirst material 250 and a second chamber 246 contains a second material252. Optionally, cap 130 is attached to partition 240 such that removalof cap 130 results in removal or partial removal of partition 240resulting in the mixture of first material 250 an second material 252.Optionally, cap 130 is not attached to partition 240 to enable separateremoval of cap 130 and partition 240. Optionally, mechanisms for partialor full removal of partition 240 are the same as those specified abovefor cap release mechanism 132. Optionally, either or both of firstchamber 244 and second chamber 246 comprise diffusion barriers such asbarrier 116 describe above.

In an embodiment, first material 250 comprises matrix 124, and AI 122.Second material 252 comprises altering material 126. Thus when partition240 is removed, second material 252 is drawn into matrix 124 and reactswith AI 122. As a non-limiting example, first material 250 comprises asponge 124 containing transfluthrin (AI 122) and second material 252 isa solvent (altering material 126). With removal of partition 240,solvent 126 wicks into sponge 124 to volatize transfluthrin 122 andcause diffusion of the mixture through membrane 114 into the air.Alternatively first material 250 comprises matrix 124, AI 122 and analtering material 126A.

Second material 252 comprises a second altering material 126B. Thus whenpartition 240 is removed, second material 252 reacts with first material250. As a non-limiting example, first material 120 comprises a sponge124 containing transfluthrin (AI 122) and a solvent (altering material126A) such as isopropanol, while second material 252 comprises anexothermic reactant (altering material 126B). With removal of partition240, exothermic reactant 126B wicks into sponge 124 to volatize thetransfluthrin solvent mixture and cause diffusion of the mixture throughmembrane 114 into a fluid such as air. In a non-limiting example, wherecap 130 is not attached to partition 240, partition 240 is fully orpartially removed for activation of an exothermic reaction as exothermicreactant 126B wicks into sponge 124 to first volatize the transfluthrinsolvent mixture, followed by removal of cap 130 after a specified timeperiod for diffusion of the mixture through membrane 114 into air.

Thus, in addition to the mechanisms listed above for controlling passiverelease of an AI, device 200 (and device 300 below) provides furtheroptions:

-   -   Changing the formulation of the first 250 and second 252        materials (and subsequent materials) to alter the evaporation        rate of the AI;    -   Controlling the permeability of partition 240 and the amount        that partition 240 is removed when cap 130 is removed from        between internal chambers 244 and 246, such as by changing any        of the effective area, thickness, or tortuosity of partition        240.

FIG. 3A and FIG. 3B show sectional illustrations of an exemplaryembodiment of a CRD with three chambers. A device 300 provides forcontrolled release of an AI. Device 300 is functionally similar todevices 100 and 200 but reservoir 110 comprises three internal chambers344, 346 and 348 divided by internal partitions 340 and 342. A firstchamber 344 contains a first material 350, a second chamber 346 containsa second material 352 and a third chamber 348 contains a third material354. Cap 130 is optionally attached to partitions 340 and 342 such thatremoval of cap 130 results in removal or partial removal of partitions340 and 342 resulting in the mixture of first material 350, secondmaterial 352, and third material 354. Optionally, cap 130 is notattached to partitions 340 and 342 to enable separate removal of cap 130and of partitions 340 and 342. Optionally, partitions 340 and 342 areremoved simultaneously or sequentially. Optionally, mechanisms forpartial or full removal of partitions 340 and 342 are the same as thosespecified above for cap release mechanism 132. Optionally, any or all offirst chamber 344, second chamber 346 or third chamber 348 comprisediffusion barriers such as barrier 116 describe above.

In an embodiment, first material 350 comprises matrix 124, and AI 122.Second material 352 comprises first altering material 126A, and thirdmaterial 354 comprises second altering material 126B. Thus whenpartitions 340 and 342 are removed second material 352 and thirdmaterial 354 are drawn into matrix 124 and react with AI 122.

As a non-limiting example, first material 350 comprises a sponge 124containing transfluthrin (AI 122), second material 352 is a solvent(altering material 126A) and third material 354 is an exothermicreactant (altering material 126B). With removal of partitions 340 and342, solvent 126A wicks into sponge 124 to volatize transfluthrin 122,and exothermic reactant 126B wicks into sponge 124 to further volatizethe transfluthrin solvent mixture and cause diffusion of the mixturethrough membrane 114 into the air.

In a non-limiting example, where cap 130 is not attached to partitions340 and 342, partitions 340 and 342 are fully or partially removed suchthat solvent 126A wicks into sponge 124 to volatize transfluthrin 122and exothermic reactant 126B wicks into sponge 124 to first volatize thetransfluthrin solvent mixture, followed by removal of cap 130 after aspecified time period for diffusion of the mixture through membrane 114into air. Optionally, the mechanism for removing partitions 340, 342prevents removal of cap 130 such that a user is forced to first removethe partitions 340, 342 before removal of cap 130.

Reference is now made to FIG. 4A which is a flowchart showing anexemplary process 400 for integrating an AI with a high melting pointinto a matrix 124. A non-limiting example of an AI that is solid at roomtemperature is transfluthrin which has a melting point of 32 degreesCelsius. In step 402 the AI is warmed past its melting point to form aliquid form of the AI. In step 404 the matrix is soaked with the liquidform of the AI. Alternatively, the matrix is cooled before exposure tothe liquid form of the AI such that the AI solidifies upon contact withthe matrix. In step 406 the AI cools and solidifies within and aroundthe matrix to form an active material. Optionally, the cooling is activerequiring but not limited to placing the soaked matrix in refrigeration.Alternatively, the cooling is passive where the soaked matrix is leftuntil it cools to room temperature. In step 408 the active material isinserted into the release device such as a reservoir of one of thedevice embodiments as described herein. As described above withreference to FIGS. 1A-1F, 2A-2B, and 3A-3B, a solvent is used forvolatizing the active material and releasing the AI from the matrix.

An alternative method is shown in FIG. 4B which is a flowchart showingan exemplary process 450 for integrating an AI with a high melting pointinto a matrix 124. In step 452 the AI is combined with a solvent toliquefy the AI. In step 454 the matrix is soaked with the combinedsolvent/AI. In step 456 the soaked sponge is warmed or placed in anenvironment such that the solvent evaporates leaving behind the AI thatsolidifies within and around the matrix to form an active material. Instep 458 the active material is inserted into the release device such asa reservoir of one of the exemplary embodiments as described herein. Asdescribed above, when the device is activated, a solvent is used forvolatizing the active material and releasing the AI from the matrix. Inthe embodiment of FIG. 4B a lower concentration of AI is impregnatedinto the matrix than in the embodiment of FIG. 4A.

FIG. 5A, FIG. 5B, FIG. 5C, and FIG. 5D show alternate views and anexploded view of an exemplary embodiment of a CRD. As shown in FIGS.5A-5D, a CRD 500 comprises a reservoir 510 with multiple chambers 518each holding an active material 520. Active material 520 is the same asactive material 120 and comprises one or more of AI, matrix and alteringmaterials. CRD 500 optionally includes an indicator 508 showing theamount of AI remaining in CRD 500. Indicator 508 is optionally a windowon device 500 with a scale and a dye calibrated to have the same orsimilar volatility as the active material 520 in each chamber to thusshow the remaining concentration of the AI in each chamber.

In the illustrations, device 500 is shown as having four chambers 518but optionally any suitable number of chambers 518 may be provided.Chambers 518 are formed within reservoir 510 by dividers 516. In theembodiment as shown, active materials 520 in each chamber 518 do notcome into contact with one another and do not mix. Optionally, dividers516 can be removed before use to enable mixing of active materials 520such as in the embodiments of FIGS. 2A-2B and 3A-3B.

Optionally, active materials 520 in each of chambers 518 are ofdiffering formulations. Optionally, each of chambers comprises pores 512for diffusion of the AI from the corresponding active material 520.Optionally, a grid 514 prevents direct contact of active material 520with pores 512. A cap 530 seals pores 512 until device 500 is to be usedand cap 530 is removed. Optionally, pores 512 of each chamber 518 arecovered by separate caps 530. In some embodiments, the number andarrangement of pores 512 are different for each chamber 518 such asshown in FIG. 5D. The illustration of FIG. 5D showing different pore 512arrangements per chamber 518 should not be considered limiting.

FIG. 5E shows a graph of exemplary dispersion rates for a CRD withmultiple chambers. The combination of differing active material 520,chamber 518 size and number/arrangement of pores 512 result in differentrelease characteristics for each chamber 518. Thus, these parameters canbe adjusted such that chambers 518 have overlapping release periods suchas in the illustrative graph of FIG. 5E showing overlapping releaseconcentrations from two chambers 518 including a large initial releasefrom a first chamber 518 for initial stronger effect of the AI.

In exemplary embodiments where each of chambers 518 contain differentformulations of active material combined with an altering material, aformulation of an AI of transfluthrin or metofluthrin mixed with avolatile organic solvent is provided with the AI in a range of 20% to95% of the formulation, and the solvent in a corresponding range of 80%to 5%. The size and arrangement of pores 512, and the percentage of AIpresent in a chamber 518 are optionally together designed to provide therequired release rates per chamber 518.

FIG. 5F and FIG. 5G show photographs of an exemplary CRD adapted forattachment to clothing. As shown in FIG. 5F, CRD 500 is shaped so as tofit into a standard issued military uniform or vest 20 having a weaving22. In FIG. 5F, CRD 500A is shown not inserted into weaving 22 in orderto clearly show the positioning of pores 512A and 512B. In FIGS. 5F-5G,CRD 500B is shown inserted into weaving 22. As shown, pores 512A and512B of device 500 are sized and positioned such that pores 512A and512B are between weaving 22 such that weaving 22 does not block pores512A and 512B. Holding clip 506 is used for positioning and easyinsertion and removal of device 500 into weaves 22. In exemplaryembodiments, the spacing between successive weaves 22 is one inch, andweaves have a height of one inch such that the height of pores 512A and512B is one inch.

FIG. 6 shows an exemplary embodiment of a CRD for releasing an activeingredient such as a larvicide into a fluid environment. Exemplarily,the fluid environment is water 40 or another liquid. In some exemplaryembodiments, controlled release larvicides are released from a floatingCRD 600 for sustained and prolonged performance such as for up to threemonths. As with device 100, device 600 comprises active material 120 andvariation of release rates of an AI are controlled as for device 100.Optionally, reservoir 610 comprises multiple chambers each withdifferent active materials that combine when the partitions between thechambers are removed such as when device 600 is deployed such as in theembodiments of FIGS. 2A-2B and 3A-3B.

The use of device 600 for controlled release of a larvicide into waterrequires that device 600 float (have buoyancy) in water 40 and that itnot get wet internally, to prevent compromising the device structure.The latter may be achieved for example by adding a super hydro/oleicphobic material layer (such as silica nano-coatings, or fluorinatedsilanes) on the outside of device 600.

Device 600 comprises an air chamber 602 that allows device 600 to float,a stabilizer 606 that maintains the position of device 600 as it floats,and pores 612 to allow the active ingredient to diffuse into water 40.As shown in FIG. 6, pores 612 release a trail 622 of AI into water 40.

FIG. 7 shows an exemplary embodiment of a CRD for deployment from aflying platform. As shown in FIG. 7, a controlled release systemdisclosed herein may be dropped from a flying platform such as a droneor a plane. FIG. 7 shows a CRD 700 hanging from a miniature parachute702. Parachute 702 includes a canopy 704 connected by strings 706 todevice 700. Canopy 704 allows device 700 to land softly on land orwater. The parachute strings 706 activate device 700 by pulling up a cap730 covering the pores 712 of device 700. Device 700 comprises an activematerial 120. Optionally, reservoir 710 comprises multiple chambers eachwith different active materials that combine when the partitions betweenthe chambers are removed such as when cap 730 is lifted such as in theembodiments of FIGS. 2A-2B and 3A-3B.

In use, as device 700 is dropped from a flying platform, increased airresistance in canopy 704 increases the pulling force on canopy strings706, opening device cap 730 and releasing the AI into the surroundingfluid (air or water). Convective forces due to wind during devicelanding increase mass transfer. By changing parachute landingparameters, a change in force convection can be achieved thus tailoringrelease rate of the AI. As shown in FIG. 7, pores 712 release a trail722 of AI into the surrounding fluid.

FIGS. 8A-8D show an exemplary embodiment of a CRD formed from a fold-upreservoir. Exemplarily, CRD 800 is in the shape of a hexagonal cardboardor paper or cellulose-based box described in co-owned U.S. design patentapplication Ser. No. 29/633,676, titled “Fold-up container/dispenserwith a floor and a dispersion platform” and filed Jan. 15, 2018. In anexemplary embodiment, the fold-up container/dispenser is a hexagonalbox, shown in FIG. 8A in a closed state and in FIG. 8B in an open state.The box is initially a flat paper or cardboard structure, FIG. 8C, that,upon folding, becomes a 3D structure as in FIGS. 8A-8B.

FIG. 8C shows hexagonal box CRD 800 in its 2D shape. Box 800 comprises abox base 802, where a floor 808 of the device will be located uponfolding. The base supports the active material 120. Device 800 furthercomprises hinge regions 804 to allow the parts to fold, box sidewalls806 to provide lateral confinement to the controlled release system, abox floor 808, where the controlled release device is positioned, ahinge region 810 to allow folding of box floor inwards and a perforatedmembrane 812 with pores 814 that provide a controlled release mechanismand that can be sized to a desired size to control release kinetics.Device 800 further comprises a hinge region 816 to allow the perforatedmembrane to fold, a foot pedestal 818 to allow the perforated membraneto anchor on top of the device without displacement, a cap 820 toprovide hermeticity to the device and avoid release of activeingredient, a pull tab 822 to allow activation of the device by breakingpre-perforations, pre-perforations 824 on cap 820 to ensure devicehermeticity until the device is activated via pull tab, and cap flaps826 to allow perforated membrane 812 to fit within the hexagonal box.The flaps arrows can be made square or circular to facilitate sealing ofdevice 800. FIG. 8D shows that pre-perforations 824 are not made throughthe entirety of the cap material (i.e. do not penetrate through cap 820from one side to the other), leaving a non-perforated section 828 inorder to minimize leakage of the AI and vapors while the device isstored.

In the claims or specification of the present application, unlessotherwise stated, adjectives such as “substantially” and “about”modifying a condition or relationship characteristic of a feature orfeatures of an embodiment of the invention, are understood to mean thatthe condition or characteristic is defined to within tolerances that areacceptable for operation of the embodiment for an application for whichit is intended.

It should be understood that where the claims or specification refer to“a” or “an” element, such reference is not to be construed as therebeing only one of that element.

In the description and claims of the present application, each of theverbs, “comprise” “include” and “have”, and conjugates thereof, are usedto indicate that the object or objects of the verb are not necessarily acomplete listing of components, elements or parts of the subject orsubjects of the verb.

While this disclosure describes a limited number of embodiments, it willbe appreciated that many variations, modifications and otherapplications of such embodiments may be made. The disclosure is to beunderstood as not limited by the specific embodiments described herein,but only by the scope of the appended claims.

What is claimed is:
 1. A controlled release device (CRD) comprising: a)a reservoir divided into a plurality of chambers by partitionspositioned between adjacent chambers, each partition having respectivepartition planes contacting the adjacent chambers; b) a first activematerial placed in a first chamber of the plurality of chambers and atleast one second active material placed in at least one other of theplurality of chambers, wherein the first active material comprises anactive ingredient (AI), wherein the at least one second active materialcomprises one or both of a matrix and an altering material, and whereinthe partitions are positioned between adjacent chambers such that fullor partial removal of at least one partition results in mixing of thefirst active material and the at least one second active material toform a mixed active material; c) a permeable membrane comprising porescovering the first chamber, wherein the respective partition planes aresubstantially perpendicular to the permeable membrane; and d) a cappositioned over the membrane for sealing the reservoir such that removalof the cap results in controlled release of the AI from the mixed activematerial through the membrane.
 2. The device of claim 1, wherein the AIis one of transfluthrin or metofluthrin and wherein the alteringmaterial of the at least one second active material is a volatileorganic solvent such that the mixed active material is volatizedtransfluthrin.
 3. The device of claim 1, wherein the AI is one oftransfluthrin or metofluthrin and wherein the altering material of afirst of at least one second active material is a volatile organicsolvent and the altering material of a second of at least one secondactive material is dimethylsulfoxide (DMSO) such that the mixed activematerial is volatized transfluthrin or metofluthrin enhanced by DMSO. 4.The device of claim 1, wherein the AI is one of transfluthrin ormetofluthrin and the first active material further comprisesdimethylsulfoxide (DMSO) for enhancing the transfluthrin wherein thealtering material of the at least one second active material is avolatile organic solvent such that the mixed active material isvolatized transfluthrin or metofluthrin enhanced by DMSO.
 5. The deviceof any one claim 2, wherein the volatile organic solvent is one ofisopropanol, ethanol, methanol, or hexane.
 6. The device of any oneclaim 2, wherein the AI is provided in a concentration of between20%-95% of the mixed active material.
 7. The device of claim 1, whereinthe altering material of a first of the at least one second activematerial is an exothermic reactant such that the mixed active materialis the AI at an increased temperature.
 8. The device of claim 1, whereinthe AI is transfluthrin and wherein the altering material of a first ofat least one second active material is a volatile organic solvent andthe altering material of a second of at least one second active materialis an exothermic reactant such that the mixed active material isvolatized transfluthrin that is further volatized by increasedtemperature caused by the exothermic reactant.
 9. The device of claim 7,wherein the exothermic reactant is provided in the form of powder orrods selected from the group consisting of iron, iron-based compounds,vermiculate (hydrated magnesium aluminum silicate), charcoal powder, andsodium chloride.
 10. The device of claim 7, wherein the exothermicreactant is an exothermic reactant that is activated when exposed tooxygen such that the exothermic reactant is activated when the cap isremoved.
 11. The device of claim 1, wherein the AI is one of aninsecticide, a spatial repellent, a herbicide or a larvicide.
 12. Thedevice of claim 1, wherein the first active material further comprisesone or both of a matrix and an altering material.
 13. The device ofclaim 12, wherein the controlled release is determined by a mechanismselected from the group consisting of changing the evaporation rate ofthe AI, changing the surface area of the matrix, changing thepermeability of the membrane, adding one or more diffusion barriers,changing the viscosity of the first active material, changing the typeof matrix, changing the temperature of the reservoir, utilizing anactive release mechanism, changing the formulation of the first activematerial, changing the formulation of the at least one second activematerial, changing the permeability of the plurality of partitions, anda combination thereof.
 14. The device of claim 1, wherein the AI isselected from the group consisting of a spatial repellent, an essentialoil, a pyrethroid, an insecticide, an organochloride, anorganophosphate, a carbamate, a neonicotinoid, a herbicide, anattractant, a larvicide, and a combination thereof.
 15. The device ofclaim 1, wherein the altering material is selected from the groupconsisting of a solvent, an encapsulator, an enhancer, an exothermicreactant, an oil and a combination thereof.
 16. The device of claim 12,wherein the matrix is selected from the group consisting of a porousmaterial, a synthetic material, a material reactive to the alteringmaterial, and a combination thereof.
 17. The device of claim 1, furthercomprising at least one diffusion barrier.
 18. The device of claim 17,wherein the diffusion barrier comprises at least one hydrophobic domain.19. The device of claim 1, further comprising a cap release mechanismselected from the group consisting of a mechanical cap releasemechanism, a breakable cap release mechanism, an electrothermal rupturerelease mechanism, an electro-thermal-stress rupture release mechanism,an ultrasound cap release mechanism, a pH-based cap release mechanism,an optical-based release mechanism, and a combination thereof.
 20. Thedevice of claim 1, wherein the device is adapted to be wearable.
 21. Thedevice of claim 1, further comprising an indicator for showing theamount of AI remaining in the device wherein the indicator comprises ascale and a dye calibrated to have the same volatility as the mixedactive material to thus show the remaining concentration of AI in thedevice.
 22. The device of claim 20, wherein the pores are positioned soas to be exposed when the device is inserted into periodically spacedweavings of a vest.